package meituan;

import java.util.Scanner;

/**
 * @author le
 */
public class Meituan3
{
    public static void main(String[] args)
    {

        Scanner in = new Scanner(System.in);
        // n杯饮料 5
        int n = in.nextInt();
        // m 个人  3
        int m = in.nextInt();
        // c 每次喝的量 4
        int c = in.nextInt();

        int[] juice = new int[n];
        for (int i = 0; i < n; i++)
        {
            juice[i] = in.nextInt();
        }

        // 5 8 3 10 7
        // 3 5 7 8 10
        // 1 2 2 2 3 = 10
        int count = 0;
        for (int i = 0;i < n;i++){
            if (juice[i] % c != 0){
                count++;
            }
            count += (juice[i]/c);
        }
        int res = 0;
        if (count % m != 0){
            res++;
        }
        res += count/m;
        System.out.println(res);


        in.close();
    }
}
